The excretory organs in Sphaerodorum flavum (Phyllodocida, Sphaerodoridae): a rare case of co-occurrence of protonephridia, coelom and blood vascular system in Annelida M. KuperGünter Purschke Original Article Pages: 191 - 203
Ultrastructure and significance of the transitory nephridia in Erpobdella octoculata (Hirudinea, Annelida) B. QuastThomas Bartolomaeus Original Article Pages: 205 - 213
Comparative investigation of the genital systems in the Opisthobranchia (Mollusca, Gastropoda) with special emphasis on the nidamental glandular system A. Klussmann-Kolb Original Article Pages: 215 - 235
Aberrant spermatogenesis and sex determination in Bourletiellidae (Hexapoda, Collembola), and their evolutionary significance R. DallaiPietro Paolo FanciulliFrancesco Frati Original Article Pages: 237 - 245